All the types of tired you can be

In a comment on the most recent Ask A Swole Woman, a reader asked me to dig a little deeper into the concept of “CNS fatigue.” It sounds like CNS fatigue has become a kind of trendy social media topic for people to do preachy, scaremongering “Just a reminder that” Instagram reels. (I beg you all: If you see these things in the wild and want me to speak on them, please please please send me the links!) But as this reader put it: “In short, I have only heard talk of ‘CNS fatigue’ from bro science, and sports science, but never from neurologists or neuroscientists. It seems like maybe it's A Thing, it just has a very unhelpful name for those of us who have neurogenic fatigue from, say, taking a shower?”
So, to borrow the parlance of our current political moment, “CNS fatigue” does not just fall out of a coconut tree. It exists in the context of all in which you live and all that came before you.
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